Reproductive Phenology of Central Amazon Pioneer Trees

This study characterizes the flowering and fruiting phenology of the 13 most common pioneer tree species in early successional forests of the Central Amazon. For each species, 30 individuals, 10 each in three secondary forests, were monitored monthly for four years at the Biological Dynamics of Forest Fragments Project, north of Manaus. Five species showed nearly continuous flowering and fruiting throughout the study, indicating that resources were available to pollinators and dispersers on a regular basis. The other eight species showed stronger seasonality in reproduction, seven of them annually, and one supra-annually. Overall, flowering was concentrated in the transition from the dry to the rainy season and fruiting was concentrated in the rainy season. There was no relationship between reproductive phenology and tree pollinator type or dispersal mode. Reproductive phenology was remarkably consistent year to year. The pioneer community showed a variety of phenological patterns but as a whole tended to be characterized by annual flowering and fruiting, either continuously or seasonally, thereby fitting generalizations of pioneer species relative to mature forest species.